Initial vendor packages

Signed-off-by: Valentin Popov <valentin@popov.link>

vendor/libc/src/hermit/aarch64.rs

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+pub type c_char = u8;
+pub type wchar_t = u32;

vendor/libc/src/hermit/mod.rs

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+//! Hermit C types definition
+
+pub type c_schar = i8;
+pub type c_uchar = u8;
+pub type c_short = i16;
+pub type c_ushort = u16;
+pub type c_int = i32;
+pub type c_uint = u32;
+pub type c_float = f32;
+pub type c_double = f64;
+pub type c_longlong = i64;
+pub type c_ulonglong = u64;
+pub type intmax_t = i64;
+pub type uintmax_t = u64;
+
+pub type size_t = usize;
+pub type ptrdiff_t = isize;
+pub type intptr_t = isize;
+pub type uintptr_t = usize;
+pub type ssize_t = isize;
+
+pub type c_long = i64;
+pub type c_ulong = u64;
+
+pub type wint_t = u32;
+pub type wctype_t = i64;
+
+pub type regoff_t = size_t;
+pub type off_t = c_long;
+
+cfg_if! {
+    if #[cfg(target_arch = "aarch64")] {
+        mod aarch64;
+        pub use self::aarch64::*;
+    } else if #[cfg(target_arch = "x86_64")] {
+        mod x86_64;
+        pub use self::x86_64::*;
+    } else {
+        // Unknown target_arch
+    }
+}
+
+cfg_if! {
+    if #[cfg(libc_core_cvoid)] {
+        pub use ::ffi::c_void;
+    } else {
+        // Use repr(u8) as LLVM expects `void*` to be the same as `i8*` to help
+        // enable more optimization opportunities around it recognizing things
+        // like malloc/free.
+        #[repr(u8)]
+        #[allow(missing_copy_implementations)]
+        #[allow(missing_debug_implementations)]
+        pub enum c_void {
+            // Two dummy variants so the #[repr] attribute can be used.
+            #[doc(hidden)]
+            __variant1,
+            #[doc(hidden)]
+            __variant2,
+        }
+    }
+}

vendor/libc/src/hermit/x86_64.rs

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+pub type c_char = i8;
+pub type wchar_t = i32;